Moon Landings

The Moon has always captured my imagination. Growing up I waved to the astronauts I assumed were toiling away on the surface, carrying out experiments. I often wondered if they could see me. It turns out that no, they couldn’t! Not because they weren’t looking at me when I waved, but because there was no one there. I was extremely disappointed to discover that the last astronaut left the surface of the Moon long before I was born.

President Kennedy declared the ambitions of the USA to go to the Moon “not because it is easy, but because it is hard.” Indeed, it was high-risk and people lost their lives on the way to the successful landings. In all, there were six missions. Neil Armstrong and Buzz Aldrin were the first in 1969. Their broadcast from the Moon was watched all around the world. Neil Armstrong’s famous words – which he actually fluffed, he missed an “a” before “man” – “One small step for man, one giant leap for mankind” rang out around the world.

Five crews followed, the last in 1972. We haven’t been back since. Instead we have sent robots, this is cheaper and safer.

But what did the Moon landings involve? What did the crews do when they got to the surface?

Escape from Earth

The crew of three – Neil Armstrong, Buzz Aldrin and Michael Collins – were thrown into Earth orbit on a Saturn V rocket. This was a monster, it had multiple engine stages to get them to the Moon. They orbited the Earth less than two times, before the rocket burned again and sent them on their way to the Moon. Following the burn, the spacecraft containing the astronauts and the lander they would use to get to the Moon separated. They had been pointed in the correct direction and pushed by the rocket. It had done its job.

Three days later, they entered orbit around the Moon. After circling the Moon around 30 times, Armstrong and Aldrin began their descent in the Lunar Module. Collins stayed on board the Command Module. However, on the descent there was a computer error. The computer was doing many parallel calculations to make a safe landing. Unfortunately it was being sent lots of data from another system that it didn’t need. This meant that it couldn’t perform all of the tasks it needed to and alarms started to ring. However, the computer software was sophisticated enough to decide which tasks it needed to complete and much to the delight of the astronauts on board, it stuck with the calculations it needed to help it land.

There was still a problem with the descent of the spacecraft. Armstrong and Aldrin could see that they were headed for a rocky area. This could mean a crash-landing and a disaster for the mission. Whilst they were not far above the ground, Armstrong took manual control of the spacecraft and with less than 30 seconds of fuel remaining, he landed the spacecraft safely. His background as an aircraft test pilot was the reason he was selected as an astronaut. He was an extremely skilled and experienced aviator.

Going for a Walk

Wearing their protective space suits, they struggled out of the Lunar Module hatch. The doorway had been redesigned and made smaller. The same principle was not applied to the packs the astronauts were wearing and it was a difficult manoeuvre. Unable to see his feet because of his equipment, Armstrong came slowly down the ladder and spoke those now familiar words. Then it was down to business. The two astronauts had a large number of tasks to perform and not much time to do them. They planted the US flag, collected rock and soil samples, mapped areas of the landing site, took pictures of their Lunar Module and played around in the low-gravity environment. They tried out various styles of moving around, Aldrin even tried out movement based on a kangaroo – but they settled on bounding around on the surface. In all, they spent just over two hours on the surface before going back into their spacecraft. Coming back they were like any travellers who go to a new place, they had souvenirs and had left some things of their own behind. The flag and scientific equipment were left on the surface. After resting, they prepared the spacecraft for launch and dealt with another mis-hap that could have affected whether or not the engine fired to get them off the surface (Aldrin broke a lever, but they were able to replace it with a pen).

So, they spent less than 24 hours on the surface and many hundreds of millions watched from Earth as they crossed an important frontier.

The following five trips continued with carrying out surveys, collecting rocks, setting up science equipment. In amongst all the serious business, they were also able to have some fun. The astronauts from Apollo 14 established the Lunar Olympics. Alan Shepard smuggled the head of a golf club and two golf balls on board and had fun trying to swing using one arm (he was limited by his space suit). His colleague Edgar Mitchell fashioned a javelin and joined in on the sporty endeavours. The following missions all brought moon buggies with them, so they were able to drive around the surface and explore further afield than before. David Scott, Commander of Apollo 15, demonstrated Galileo’s proposition that all objects fall at the same rate, regardless of their mass. He dropped a hammer and feather together and because there was no air on the moon to hold the feather up, they both dropped to the floor at the same time. You can watch it here.

Sadly, we haven’t been back to the Moon since. However, there are countries around the world looking at travelling to the Moon and there are several commercial companies that are preparing their own trips. There are lots of sources of information about the Moon landings and you can watch back their broadcasts on YouTube. Hopefully we’ll see some humans back there before long. You may even know the people who go…